A power tool can be generally thought of as a tool that is powered by an electric motor, a compressed air motor, an internal combustion engine, direct burning of fuels and propellants. Power tools can be classified as either stationary or portable (i.e., a handheld device). Power tools are used in a wide variety of settings including in industry, in construction, and around the house for driving, drilling, cutting, shaping, sanding, grinding, polishing, painting, and heating. Stationary power tools are also sometimes referred to as machine tools and can come in a number of different forms, including drill presses, table saws, etc. and are designed to be fixed in one location during use. In contrast, portable power tools are mobile and can be used in different settings where movement and repositioning of the tool is necessary. For example, common power tools include but are not limited to a power drill, various types of saws, a router, an electric sander, a lathe, an electric staple gun, etc.
In terms of electric or motor driven power tools, the tools can either be wired and plugged into an electrical outlet or they can be of a cordless type and powered by a battery pack or the like. Cordless power tools offer maximum versatility as they allow the worker maximum mobility and allow the power tool to be positioned at a number of different positions without worrying about a power cord, etc.
Typically, at a worksite, more than one tool is being used to complete a project. For example, a saw, hammer and power drill can all be used at the same time to cut wood and fasten cut pieces of wood together. In addition, it is commonplace for a worker to have some type of writing implement at the worksite. For example, the most common writing implement is a carpenter pencil which is a pencil that has a body with a rectangular or elliptical cross-section to stop it from rolling or blowing away in a wind gust. Carpenter pencils offer a better grip than a standard pencil. They have a rectangular or elliptical core which allows thin or thick lines to be drawn by simply rotating the pencil. Thin lines are required for high precision markings, and when it is important to erase the markings later. There are times when thick markings are needed to make marks on a rough, course surface. The pencil must be robust enough to survive in busy construction environment.
As is known, pencil sharpeners include various devices that sharpen wood/composite pencils and also often times house the pencil shavings and chipped lead or graphite for later disposal. Prior portable pencil sharpeners are dependent upon manual manipulation to create the sharpened pencil tip. Small, battery powered units are too bulky to be carried on the body of the user and are not convenient to use. Pencils sharpened by manual methods, such as a knife, do not easily produce finely shaped tapered points and can involve a degree of risk of injury.
Carpenter pencils are typically manually sharpened with a knife, because their shapes make them unable to fit into a mechanical pencil sharpener and also because ordinary rotating sharpeners sharpen the core into round and not into desired flat shape.
There is therefore, a need for a pencil sharpener that can be powered by an external source, such as a portable power tool. U.S. Pat. No. 6,237,656 describes a pencil sharpener bit that is for use with a portable electric powered drill. However, this solution is still not entirely satisfactory and fails to address all the needs since the drill bit is a separate part that needs to be attached to the electric powered tool and needs to be safely stored when not in use, etc. What is needed is a means for sharpening a pencil (carpenter's pencil) that is integral to the power tool itself.